Magnetic write head having a shield that extends below the leading edge of the write pole

Abstract

A magnetic write head for perpendicular magnetic recording that has a write pole and a trailing or side shield that has a leading edge that extends to or beyond the leading edge of write pole, thereby ensuring complete side magnetic shielding. The write head can be formed by forming the write pole on a non-magnetic substrate that is constructed of a material that can be readily removed by reactive ion etching (RIE). The write pole can be formed by depositing a layer of magnetic write pole material over the substrate and then forming a mask over the magnetic write pole material. An ion mill can be performed to define the write pole, and then a reactive ion etch can be performed to notch the substrate, so that when a non-magnetic shield gap material is deposited it will be below or at the bottom of the write pole. Then a magnetic shield material can be deposited to form a shield having a leading edge that extends beyond the leading edge of the write pole.

Description

FIELD OF THE INVENTION[0001]The present invention relates to perpendicular magnetic recording and more particularly to a method for manufacturing a write head for perpendicular magnetic recording that has a trailing shield that extends beyond the leading edge of the write pole.BACKGROUND OF THE INVENTION[0002]The heart of a computer's long term memory is an assembly that is referred to as a magnetic disk drive. The magnetic disk drive includes a rotating magnetic disk, write and read heads that are suspended by a suspension arm adjacent to a surface of the rotating magnetic disk and an actuator that swings the suspension arm to place the read and write heads over selected circular tracks on the rotating disk. The read and write heads are directly located on a slider that has an air bearing surface (ABS). The suspension arm biases the slider toward the surface of the disk, and when the disk rotates, air adjacent to the disk moves along with the surface of the disk. The slider flies o...

AI Technical Summary

Benefits of technology

[0012]The shield can be either a trailing shield that wraps around the write pole to include side shield portions or can be purely a side shield that extends laterally to either side of the write pole without providing a trailing shield function. The write pole is constructed upon a substrate that can be readily removed by reactive ion etching, this allows the substrate itself to be notched by a reactive ion etch without damaging the write pole by an extended ion milling.

[0013]The side portions of the shield prevent tray fields from writing outside of the desired trackwidth, and because the side portions of the shield extend to or beyond the leading edge of the write pole, this side shield completely shields the medium from these side fields. If the shield is also constructed as a trailing shield, the trailing portion increases the field gradient by drawing the write field toward it.

[0014]The notching of the substrate advantageously allows the write gap material to be deposited such that the top surface of the write gap material over the substrate is at or below the bottom surface (leading edge) of the write pole. A magnetic material can then be deposited to form a magnetic shield that extends beyond the bottom (or leading edge) of the write pole.

Problems solved by technology

One feature of perpendicular recording systems is that the low coercivity underlayer of the magnetic medium is particularly susceptible to stray magnetic fields.

Unintended magnetic fields, such as from structures of the write head other than the write pole and even coming from the sides of the write pole itself can inadvertently write to portions of the medium that are outside of the intended trackwidth.

Another feature of perpendicular magnetic systems is that the magnetism of the high coercivity magnetic medium can be difficult to quickly switch.

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